Photographic developer composition



Patented Aug. 3, 1954 PHOTOGRAPHIC DEVELOPER COMPOSITION Charles V. Wilson, Rochester, N. Y., assignor to Eastman Kodak CompanygRochester, N. Y., a corporation of New Jersey No Drawing. Application August 3, 1953, Serial No. 372,192

9 Claims. 1

This invention relates to photographic developers and particularly to methods for accelerating the development rate of photographic developing agents.

I have discovered a method for accelerating the development activity of developing agents which are themselves weak developing agents for silver halide even under the most favorable conditions of development. For example, gallic acid is a very weak developing agent and the 3- pyrazolidone compounds are comparatively weak developing agents. However, I find that when these developing agents are combined in a single developing solution, the activity of the resulting developing solution is much greater than expected from summing up the separate development activities of the compounds. -A further characteristic of the gallic acid-pyrazolidone developer compositions of the invention resides in the fact that the compositions behave as strong surface latent image developers as opposed to internal latent image developers, as long as they are free of silver halide solvents. The developers also exhibit relatively little tendency for physical development. For these and other reasons, the developers of the invention are very useful in color development processes where a black-andwhite developer is required.

An additional unexpected feature of the developers containing gallic acid and the S-pyrazolidone compounds resides in the fact that similar developer compositions can be prepared, in which the pyrazoliclone is replaced by a conventional developing agent, for example, containing a mixture of N-methyl-p-aminophenol and gallic acid, which compositions do not exhibit the mentioned development acceleration efiect.

The 3-pyrazolidone developer compositions of the invention containing gallic acid can be readily converted to internal latent image developer compositions by merely adding a silver halide solvent such as sodium thiosulfate thereto.

The 3-pyrazolidone silver halide developing agents employed in the developer compositions together with gallic acid have the general structure ill in which the R groups each represent various substituents such as hydrogen, alkyl or aryl groups, for example, R1 can be hydrogen or a group such as alkyl preferably containing from 1 to a carbon atoms, or an aryl group of the benzene or naphthalene series substituted or not, and R2, R3, R4 and R5 can be hydrogen atoms, or groups such as an alkyl group preferably of 1 to 4 carbon atoms or aryl such as phenyl.

The following compounds are representative of 3-pyrazolidone silver halide developing agents which are useful in the developer compositions of the invention:

. 1-phenyl-3-pyrazolidone l-p-tolyl-3-pyrazolidone 5-phenyl-3-pyrazolidone 5-methyl-3-pyrazolidone 1-p-chlorophenyl-3-pyrazolidone 1-phenyl-5-phenyl-3-pyrazolidone l-m-tolyl-3-pyrazolidone 1-phenyl-5-methyl-3-pyrazolidone 1-p-tolyl-5-phenyl-3-pyrazolidone l0. 1-m-tolyl-3-pyrazolidone 11. 1-p-methoxyphenyl-3-pyrazolidone 12. 1-acetamidophenyl-3-pyrazolidone l3. 1-phenyl-2-acetyl-4A-dimethyl 3 pyrazo1i-- done 7 l4. 1-phenyl-4,4-dimethyl-3-pyrazolidone 15. 1 m aminophenyl 4 methyl-i-propyl 3- pyrazolidone 16. 1-o-chlorophenyl-4-methyl-4-ethyl-3-pyrazolidone l7. 1 m acetamidopheny1-4,4-diethyl-3-pyrazolidone 18. l-p(c hydroxyethylphenyl) -4,4-dimethyl-3- pyrazolidone 19. 1-p-hydroxyphenyl-4,4-dimethyl-3-pyrazolidone 20. l-p-methoxyphenyl 4,4 diethyl-3-pyrazolidone 21. l-p-tolyl-4,4-dimethyl-3-pyrazolidone 22. 1-(7 hydroxy 2 naphthyl) -4-methyl-4-npropyl-3-pyrazolidone 23. 1-p-diphenyl-4,4-dimethyl-3-pyrazolidone 24. l-p- (p-hydroxyethylphenyl) -3-pyrazolidone 25. l-o-tolyl-S-pyrazolidone 26. l-o-tolyl-A-dimethyl-3-pyrazolidone The 4,4-dialkyl-3-pyrazolidone compounds 13 to 23 and 26 above are particularly efiicacious for use in the developer compositions of my invention inasmuch as they are more active developing agents than are compounds 1 to 12 which contain a single substituent or only hydrogen atoms in the 4-position of the pyrazolidone nucleus. The 4,4-dialkyl-3-pyrazolidone compounds are described and claimed in the Allen et al. U. S. patent application Serial No. 372,148 filedconcurrently herewith. The w-hydroxyalkyHi -pyrazolidones, for example, compounds 18 and 24 above, are also especially useful in concentrated formulas, in replenishers and in the presence of high salt concentrations where their increased solubility enables obtaining and holding adequate amounts of the pyrazolidone compound in solution. The compounds are described and claimed in the Allen et a1. U. S. patent application Serial No. 372,148 filed concurrently herewith and in the Reynolds and Tinker U. S. patent application Serial No. 372,167 filed concurrently herewith.

Example 1 A fine-grain positive film was exposed behind a step wedge and separate strips were developed for a series of times in the following solutions Formula No.

Water cc. 100 100 100 Gallic acid "grams. 0. 34 i 0. 34 l-Phenyl-4,4-dimethyl-S-pyrazolidoue grams 0. 04 0. 04 Sodium sulfite, anhydrous .d 2. 5 2. 5 2. 5 Sodium carbonate, monohydrate. do 2.5 2. 5 2. 5 Acetic acid, to adjust pH to 10.0.

Formula 6585, in which gallic acid was the sole developing agent, produced no development in times up to eight minutes at 68 F. Formula 6586, containing l-phenyl-eA-dimethyl-li-pyrazolidone as a developing agent built up density very slowly. Formula 6587, containing both agents, develops vigorously and density and contrast came up rapidly. In a comparison of density produced in eight minutes at 68, developer 6585 showed no image; developer 6586 gave a density at the fourth exposure step of 0.64. and a gamma of 0.88; and developer 6587 gave a density at the fourth step of 2.66 and a gamma of 2.0.

These data illustrate the pronounced acceleration in development obtained by use of the pyrazolidone-gallic acid developer.

Example 2 The following developer compositions are useful as negative developers for color films:

(1) Without sulfite Grams/liter Sodium hexametaphosphate 0.5 Sodium carbonate monohydrate 25.0

Water to make 1.0 liter.

The developers of this example can be used in any of the well-known processes of color development where a black-and-white developer is required. The developers are especially useful in mixed grain color processes employing films such as disclosed in Mannes et al. U. S. Patent 2,388,855 or in the Carroll et al. U. S. Patent 2,614,925, October 21, 1952, wherein, for example,

is shown a two-layer film, one layer containing blue-sensitive silver halide, the other containing a mixture of green and red-sensitive silver halide grains. When the developers immediately above are used in the color process of the patents as the negative developer for such a film it is observed, particularly with the formula free of sulfite, that physical development effects are minimized with the result that the color developed images have increased saturation because of decreased physical development in the negative developer of the invention.

Results similar to those exemplified above are obtained when developer compositions, containing or free of silver halide solvents, are prepared from a mixture of at least one of the mentioned pyrazolidone compounds and gallic acid. Particularly valuable developer compositions in addition to those exemplified above are those containing gallic acid and either a 1-tolyl-3-pyrazolidone such as 1-p-tolyl-3-pyrazolidone or l-ptolyl-4A-dimethyl-3-pyrazolidone or a l-(p-hydroxyalkylphenyl-4,4-dialkyl 3 pyrazolidone, such as l-(p-fi-hydroxyethylphenyl) AA-climethyl-S-pyrazolidone, or a l-(p-hydroxyalkylphenyl) -3-pyrazolidone such as 1-(p-B-hydroxyethylphenyl) -3-pyrazolidone.

It will be understood that my invention as specified by the claims hereinafter, includes the mentioned developer compositions in either the liquid form exemplified above, or in the dry powder form such as packaged developer formulas suitable for dissolving in water to form a liquid developer. Such dry compositions include the mentioned 3-pyrazolidone compounds, gallic acid, and an alkaline material such as sodium carbonate, caustic alkali or sodium perborate.

What I claim is:

1. A photographic developer composition comprising an alkaline material, gallic acid, and a 3-pyrazolidone silver halide developing agent.

2. A photographic developer composition comprising an aqueous alkaline solution containing a mixture of gallic acid and 1-phenyl-3-pyrazolidone.

3. A photographic developer composition comprising an aqueous alkaline solution containing a mixture of gallic acid and a 4,4-dialkyl-3- pyrazolidone silver halide developing agent.

4. A photographic developer composition comprising an aqueous alkaline solution containing a mixture of gallic acid and l-phenyl-d/l-dimethyl-3-pyrazolidone.

5. A photographic developer composition comprising an aqueous alkaline solution containing a mixture of gallic acid and a 1- (w-hydroxyalkylphenyl) -3-pyrazolidone.

6. A photographic developer composition comprising an aqueous alkaline solution containing a mixture of gallic acid and 1- (p-B-hydroxyethylphenyl) -3-pyrazolidone.

7. A photographic developer composition comprising an aqueous alkaline solution containing a mixture of gallic acid and 1-(p-[3-hydroxyethylphenyl) -4,4-dimethyl-3-pyrazolidone.

8. A photographic developer composition comprising an aqueous alkaline solution containing a mixture of gallic acid and a 1-tolyl-3-pyrazolidone silver halide developing agent.

9. A photographic developer composition comprising an aqueous alkaline solution containing a mixture of gallic acid and l-p-tolyl-3-pyrazolidone.

No references cited. 

1. A PHOTOGRAPHIC DEVELOPER COMPOSITION COMPRISING AN ALKALINE MATERIAL, GALLIC ACID, AND A 3-PYRAZOLIDONE SILVER HALIDE DEVELOPING AGENT. 